Machine tool for cutting longitudinal groove in cylindrical work piece

ABSTRACT

A machine tool for forming longitudinal grooves in a cone apex of cross slot-engine lathes or similarly designed work pieces, and retaining a work piece in a clamping chuck, and a rotating cutter tool. The latter cuts into the work piece in longitudinal direction of the latter. The cutter tool comprises a fly cutter. Means are provided for continuous rotation of the work piece. The cutter tool cuts into the work piece.

United States Patent 1 1 Lieser 1 Feb. 13, 1973 MACHINE TOOL FOR CUTTING[56] References Cited LONGITUDINAL GROOVE IN T D AT S PA E T CYLINDRICALWORK PIECE E ST E T N S 75 Inventor: K Lieser, wuppert'aLElbel-feld,2,622,484 12/1952 Birrell ..90/3 3,301,135 1/1967 Jenkins ..90/15Germany 1,485,687 3/1924 Mellmg ..90/l1 R X [73] Assignee: Firma HermannWerner, Wuppertm'Hahne'berg, Germany Primary Examiner-(iii Weidenfeld 22Filed; April 24 1970 Attorney-Ernest G. Montague [21] App1. No.: 31,616[57] ABSTRACT A machine tool for forming longitudinal grooves in a [30]Foreign Apphcatlon pnomy Data cone apex of cross slot-engine lathes orsimilarly April 26, 1969 Germany P 19 21 514.6 designed work pieces, andretaining a work piece in a g clamping chuck, and a rotating cuttertool. The latter C| 90/21 cuts into the work piece in longitudinaldirection of 82/18 the latter. The cutter tool comprises a fly cutter.[51] Int. Cl ..B23c 3/28 Means are provided for continuous rotation ofthe [58] Flew of Search 1 l 1 31 work piece. The cutter tool cuts intothe work piece.

90/15, DIG. 4, 9, 5; 82/18 8 Claims, 10 Drawing Figures PATENTEDFEB 13ms 3,715,956

SHEET 10F 6 Fig. I

INVENTOR.

PATENTEDFEB13 r975 SHEEI 2 [IF 6 INVENTOR.

PATENTEU FEB 1 3 I975 SHEET 3 OF 6 v a mm mm 8% 8 Wm Q M i lilvENTOR.

PATENTEDFEB13 I975 3.715.956

SHEET u UF 6 Fig. 4

INVENTOR.

PATENTED FEB 1 3 ma SHEET 5 OF 6 VENTOR.

PATENTEUFEB13 I975 3,715,956 SHEET 6 OF 6 IN VE N TOR.

MACHINE TOOL FOR CUTTING LONGITUDINAL GROOVE IN CYLINDRIC AL WORK PIECEThe present invention relates to a machine tool for cuttinglongitudinal'grooves in the apex of a cone of cross slot-engine lathesor similar design work pieces.

It is known to work the grooves in theapex of the cone in the shaft ofan engine lathe by means of a profile cutter of conventional design. Oneuses thereby a machine tool in which the work piece is retained in aclamping chuck and the rotating cutter enters, in the longitudinaldirection of the clamped work piece, into the latter, whereby the workpiece to be formed with a plurality of grooves is set-off, stepwise uponfinishing one groove, for the angle of a groove pitch. A multipleadvance and return is thus necessary, so that the working time period isunfavorably long.

It is one object of the present invention, to provide a machine toolwhich permits. a time period for the cutting which is reduced to anappreciable extent, and which machine tool assures with an automaticcontrol working procedure, a more precise of the working.

It is another object of the present invention, to provide a machine toolwherein a cutter, formed as a fly cutter, cuts into the continuously androtatingly driven work piece.

In accordance with the present invention, the rotation of the clampingchuck and of the cutter head can be made adjustable by a common controldrive.

Furthermore, in accordance with the present invention, the advance ofthe clamping chuck can be branched-off from the same control drive, sothat a simple structure results.

In order to obtain a high cutting output by the fly cutter, inaccordance with the present invention, a sub stantially triangularcross-section profile of the fly cutter is provided which is narrowerthan the cross-section of the grooves to be produced.

In accordance with the present invention, the clamping chuck is providedon a slide controlled by a cam disc, and the jaws thereof arecontrollable, against spring forces which bias the chuck into theclamping position, by means of hydraulically or pneumatically operatedknee levers, for releasing the chuck, and thereby additionally a rapidwork piece change is obtained.

The advantages of the design of the present invention resides in thefirst place in the fact, that due to the continuous work piece rotation,the grooves as well as their pitch distance are worked exactly to thehighest degree. Furthermore, the working of the work pieces consistingmostly of high alloy steels is more favorable by the fly cutter. One canincrease the chip removal; one can obtain high cutting speeds; and onecan save on tool costs. The structure of the machine tool of this typeis less cumbersome, extremely reliablein operation, and free fromdisturbances, so that a simple automation of the working procedure canbe performed easily.

With these and other objects in view, which will become apparent in thefollowing detailed description,

the present invention, which is disclosed by example only, v villbeclearly understood in connection with the accompanying drawings, inwhich:

FIG. 1 is a perspective front view of a machine tool, designed inaccordance with the present invention;

. FIG. 2 is a perspective end view, shown at an enlarged scale;

FIG. 3 is a vertical longitudinal section of the machine tool, extendingin the plane of the clamping chuck;

FIG. 4 is a horizontal section extending in the central plane of thesupport carrying the clamping chuck;

FIG. 5 is a schematic presentation of the cutter indicating the cutterworking step of the first cut of the work piece;

FIG. 6 is a top plan view of the showing in FIG. 5;

FIG. 7 is a schematic end view of the work piece indicating the flycutter engagement;

FIG. 8 is a longitudinal plan view of the cutter head;

FIG. 9 is a bottom plan view thereto; and

FIG. 10 is an end view of the showing in FIG. 8.

Referring now to the drawings, the machine tool comprises a box typestand 1, in which the control drive RG, to be discussed below, iscontained, and which carries on a table face 2, guided for longitudinaldisplacement, a support 3 including a clamping chuck 4. At the fore-endof the table face 2, the cutter head 6 carrying the fly cutter 5 isrotatably mounted. The cutter head 6 is supported by a centering point7, which is retained'in an immovable tailstock.

Suitable grooves are worked in the cone-apex of a work piece 9 for theknown cross slot-engine lathes, and the work piece is retained clampedin the clamping chuck 4.

A transparent protecting hood 11 displaceable on rails 10 serves tocover the working against flying chips.

The support 3 including the clamping chuck 4, is reciprocable on thetable face 2. The clamping chuck 4 is continuously rotatingly driven.Likewise, the cutter head 6 is also continuously rotatingly driven bymeans ofthe cutter shaft 12, and in particular, forcibly, by means ofthe drive RG contained in the box type stand I. The main shaft 13 of thedrive carries for this purpose a bevel gear 14, which meshes with thebevel gear 15 on the cutter shaft 12. The main shaft 13 of the drive isin rigid connection with an intermediate shaft 17 of a switchablecontrol drive by means of a pair of spur gears 16, the step gears 18 ofwhich control drive are in mesh by means of a pair of sliding gears 19of an auxiliary shaft 20. Additional step gears serve the purpose ofobtaining a greater number of transmissions.

On a driven shaft 20' which extends parallel with the auxiliary shaft 20and is driven by the latter, belt pulleys 21 and 22 are secured, whichprovide by means of chains 23 and 24, respectively, or V-belts, adriving connection to the clamping chuck 4 and to the support A bushing4 of the clamping chuck 4 formed with a shaft is rotatably mounted onthe support 3 and carries a toothed gear 25, which (as shown in FIG. 4)meshes with a toothed gear 26, which sits on the drive shaft 27. Thedrive shaft 27 is telescopically expandable and formed as a cardanjoint. It carries at its free end, a chain wheel 28, on which runs thechain 23 and transmits a rotary drive.

The jaws of the clamping chuck 4 designed in form of clamping tongueshave an extended socket projection 29 which is equipped with a threadand in which a control rod 30 is screwed in. Between a spring plate 31carried by the latter and the shaft end of the bushing 4' sits a set ofplate springs 32 under pre-tension. The latter causes by its pressureforce the clamping of the jaws of the clamping chuck by pulling theconical faces thereof into the bushing 4.

In an axial arrangement of the clamping chuck 4 there is provided ahydraulic cylinder 33, the piston rod of which acts upon a double pairof knee levers 34, the end piece 35 of which abuts the control rod 30.Upon operation of the cylinder 33, the jaws of the clamping chuck arereleased by the pressure force pushing out from the bushing 4'.

The support 3 carrying the clamping chuck 4 is displaceably mounted in aprism guide 36 on the upper plate 2 of the box type stand 1. A pin end37 of the support 3 enters a ram 38, the roller of which engages a camdisc 39. The latter transmits by its rotation, the advance of theclamping chuck and of the work piece clamped therein during theoperation of the fly cutter. The cam disc 39 is provided on a shaft 40,which is mounted in the plate 2' and carries a worm wheel 41 whichengages the worm on the shaft 42. The shaft 42 has a pulley 43 on whichruns the V-belt 24, driving the cam disc 39.

The fly cutter (FIGS. 8 is disposed in a cutter head 6. The latter isrigidly connectable by its flange 44 with a cutter shaft 12. An exactcentering of the cutter head 6 takes place by a centering pin 45fittingly entering the cutter shaft and by a center drill 46, providedat the upper end, into which center drill 46 enters the center point 7of the pinole 8. The latter is carried by a .strong immovable holdingcolumn 47. The fly cutter 5 comprises a high speed plate with an edge 5'of substantially triangular cross-section-profile (FIG. 7). This profileis dimensioned corresponding with the desired groove profile, whereby itis taken into consideration, that from the entrance up to the removal ofthe cutter a rotation of the work piece takes place; thus the profilemust be also smaller than the full groove cross-section. For setting,adjustment and after-positioning, the fly cutter is lined by asupporting tooth 48, which permits by means of a set screw 49a therequired adjustment. It is fixed by clamping screws.

The operation of the described machine tool for the working oflongitudinal grooves within the range of the apex of the cone of a workpiece will now be explained in connection with FIGS. 57 of the drawings:

The work piece change is performed while the protection hood 1] (FIG. 1)is in open position. The work piece 9 comprises a bolt or shaft which isforcibly inserted into and withdrawn from, respectively, the receivingcavity of the jaws of the clamping chuck 4. A suitably providedautomatic program circuit performs the machine control. For the start ofthe latter, the protection hood is to be closed and a starting switch isto be operated. By this operation, the joint control drive RG isstarted. The cutter shaft 12 is driven with a number of revolutions n.Simultaneously, the clamping chuck 4 is tightened and is put into acontinuous rotation n" by means of the chain drive 21, 23 and 28 and thedrive shaft 27 in addition to the gear transmission 25 and 26, whichcontinued rotation 51 is sychronous with the cutter shaft 12, however,at a ratio corresponding with the desired number of grooves (in theshown example 1:4).

By the cam disc 39, the support 3 is moved in a direction towards thecutter head 6, likewise in synchronism, by the belt drive 22 and 24, andin par- 4 cutter 5 on the conical face of the work piece 50 begins itscutting insertion during the working, and deepens the cut withprogressing advance, whereby the work piece rotation during the cutterengagement, produces a cross-section of the groove 51, as seen in FIG.7.

By the continuous and ratio-synchronous rotation of the work piece 50,during each rotation successively each of the grooves 51, for example,four grooves, is cut. As it is shown in FIG. 5, at first the cutterpoint of the triangular fly cutter 5 cuts on the conical jacket face andimmerses deeper, as longas a stroke takes place in the direction of thearrow x. This makes possible a favorable chip formation and a freecutting of the cutter, so that the highest cutting speeds areapplicable.

The dotted-dashed line curves of the grooves in FIG. 6 indicate theexpansion of the groove out within the range of the conical point uponadvance during the working-in. In this figure, also the finished form ofthe groove is recognizable on a four grooved cross-slot-engine lathe.The cross ribs remaining between the grooves constitute preciselycoinciding drives as to form and position, which must enter exactly intothe slots of the screw head.

Instead of the illustrated shaft end of a cross slot-engine lathe,similarly formed work pieces can be produced for other purposes, byexample, inserts for ratched-like engine lathes, under circumstancesalso with a greater number of grooves. Likewise the length of thegrooves and the cone point can be varied.-

While I have disclosed several embodiments of the present invention, itis to be understood that these embodiments are given by example only andnot in a limitticular so far that the working-in of the grooves into the6 work piece takes place. As schematically shown in FIGS. 5, 6 and 7,the working of the edge 5' of the fly ing sense.

I claim:

1. A machine tool for cutting longitudinal grooves having theconfiguration of a cone apex on a cylindrical work piece, comprisingchuck means for clamping the work piece therein,

means supporting said chuck means for rotation about an axis,

means mounting a cutting tool for rotation about an axis substantiallynormal to the rotational axis of said chuck means, 4

said cutting tool comprising a fly cutter extending into the path of thework piece,

joint control means for rotating said chuck means and said cutting tool,said joint control means rotating said cutter tool at a predeterminedrate proportional to the rotational speed of said chuck means, and 7means associated with said joint control drive means for providingrelative movement between the chuck means and the cutting tool in thedirection of the rotational axis of I said chuck means, whereby saidlongitudinal grooves are cut into said work piece.

2. The cutting machine, as set forth in claim 1,

wherein said means associated with said control drive means advancessaid chuck means toward said cutting tool. I

3. The machine tool, as set forth in claim 1, wherein said fly cutterhas a substantially triangular cross-section-profile andis narrower thanthe cross-section of the grooves to be produced in said cone apex,

said clamping chuck including jaws for holding said work piece,

said means for providing relative movement between said chuck means andsaid cutting tool including a slide member supporting said clampingmeans for movement towards said cutting tool and a cam disc cooperatingwith said slide member for controlling the movement thereof,

spring means for urging said jaws into a work piece clamping position,and

hydraulically operated knee lever means for controlling said jaws into areleasing position.

4. A cutting machine for cutting grooves having the configuration of acone apex on a work piece, comprising a chuck means for releasablyretaining said work piece projecting from said chuck means,

means supporting said chuck means for rotation about an axis,

means mounting a cutting tool means for rotation about an axissub-stantially normal to the rotational axis of said chuck means,

means for rotating said cutting tool means at a predetermined rateproportional to the rotational speed of said chuck means,

said cutting tool means comprising a single knife extending into thepath of said work piece,

said knife being triangular in cross-section and defining a knife edge,and

said means for rotating said cutting tool displacing said knife edgeduring a portion of said rotation thereof in the direction of therotational axis of said chuck means into cutting engagement with saidwork piece while the latter is continuously rotated, whereby successiveprofile cuts widen said grooves into said cone apex.

5. The cutting machine, as set forth in claim 4, wherein said knife edgeconstitutes a pointed edge of said triangular cross-section of the knifeand said triangu-' lar cross-section is narrower than the profile of thegrooves to be worked into said cone apex.

6. The cutting machine, as set forth in claim 4, wherein said means forrotating said cutting tool means includes a cutter shaft on which saidcutting tool means is secured,

a main shaft disposed at a right angle to said cutter shaft anddrivingly connected thereto,

a slide,

said chuck means constituting a clamping means for releasably retaininga rod-like work piece,

said means supporting said chuck means mounted on said slide,

step drive gear means operatively connected to said main shaft forrotating said means supporting said chuck means and said work piece suchas to provide a selectively variable continuous rotation of said cuttingtool relative to the continuous rotation of said work piece.

7. The cutting tool, as set forth in claim 4, wherein said means forrotating said cutting tool means includes a cutter shaft on which saidcutting tool means is secured,

a main shaft disposed at a right angle to said cutter shaft anddrivingly connected thereto, a slide on which said means supporting saidchuck means is disposed,

a cam 'means for longitudinally displacing said means supporting saidchuck means,

said chuck means having inner clamping members,

spring means for biasing said inner clamping members into a clampinglocking position for retaining said work piece, and

hydraulically operated knee lever means for moving said inner clampingmembers against the force of said spring means into a releasingposition.

8. The cutting machine, as set forth in claim 4,

further comprising a slide on which said means supporting said chuckmeans is disposed,

said slide disposed for movement parallel to the direction of therotational axis of said chuck means,

said means supporting said chuck means and said means for rotating saidcutting tool constitute a control drive means including transmissionstep gears, and

separate drive means for moving said slide.

1. A machine tool for cutting longitudinal grooves having theconfiguration of a cone apex on a cylindrical work piece, comprisingchuck means for clamping the work piece therein, means supporting saidchuck means for rotation about an axis, means mounting a cutting toolfor rotation about an axis substantially normal to the rotational axisof said chuck means, said cutting tool comprising a fly cutter extendinginto the path of the work piece, joint control means for rotating saidchuck means and said cutting tool, said joint control means rotatingsaid cutter tool at a predetermined rate proportional to the rotationalspeed of said chuck means, and means associated with said joint controldrive means for providing relative movement between the chuck means andthe cutting tool in the direction of the rotational axis of said chuckmeans, whereby said longitudinal grooves are cut into said workpiece.
 1. A machine tool for cutting longitudinal grooves having theconfiguration of a cone apex on a cylindrical work piece, comprisingchuck means for clamping the work piece therein, means supporting saidchuck means for rotation about an axis, means mounting a cutting toolfor rotation about an axis substantially normal to the rotational axisof said chuck means, said cutting tool comprising a fly cutter extendinginto the path of the work piece, joint control means for rotating saidchuck means and said cutting tool, said joint control means rotatingsaid cutter tool at a predetermined rate proportional to the rotationalspeed of said chuck means, and means associated with said joint controldrive means for providing relative movement between the chuck means andthe cutting tool in the direction of the rotational axis of said chuckmeans, whereby said longitudinal grooves are cut into said work piece.2. The cutting machine, as set forth in claim 1, wherein said meansassociated with said control drive means advances said chuck meanstoward said cutting tool.
 3. The machine tool, as set forth in claim 1,wherein said fly cutter has a substantially triangularcross-section-profile and is narrower than the cross-section of thegrooves to be produced in said cone apex, said clamping chuck includingjaws for holding said work piece, said means for providing relativemovement between said chuck means and said cutting tool including aslide member supporting said clamping means for movement towards saidcutting tool and a cam disc cooperating with said slide member forcontrolling the movement thereof, spring means for urging said jaws intoa work piece clamping position, and hydraulically operated knee levermeans for controlling said jaws into a releasing position.
 4. A cuttingmachine for cutting grooves having the configuration of a cone apex on awork piece, comprising a chuck means for releasably retaining said workpiece projecting from said chuck means, means supporting said chuckmeans for rotation about an axis, means mounting a cutting tool meansfor rotation about an axis sub-stantially normal to the rotational axisof said chuck means, means for rotating said cutting tool means at apredetermined rate proportional to the rotational speed of said chuckmeans, said cutting tool means comprising a single knife extending intothe path of said work piece, said knife being triangular incross-section and defining a knife edge, and said means for rotatingsaid cutting tool displacing said knife edge during a portion of saidrotation thereof in the direction of the rotational axis of said chuckmeans into cutting engagement with said work piece while the latter iscontinuously rotated, whereby successive profile cuts widen said groovesinto said cone apex.
 5. The cutting machine, as set forth in claim 4,wherein said knife edge constitutes a pointed edge of sAid triangularcross-section of the knife and said triangular cross-section is narrowerthan the profile of the grooves to be worked into said cone apex.
 6. Thecutting machine, as set forth in claim 4, wherein said means forrotating said cutting tool means includes a cutter shaft on which saidcutting tool means is secured, a main shaft disposed at a right angle tosaid cutter shaft and drivingly connected thereto, a slide, said chuckmeans constituting a clamping means for releasably retaining a rod-likework piece, said means supporting said chuck means mounted on saidslide, step drive gear means operatively connected to said main shaftfor rotating said means supporting said chuck means and said work piecesuch as to provide a selectively variable continuous rotation of saidcutting tool relative to the continuous rotation of said work piece. 7.The cutting tool, as set forth in claim 4, wherein said means forrotating said cutting tool means includes a cutter shaft on which saidcutting tool means is secured, a main shaft disposed at a right angle tosaid cutter shaft and drivingly connected thereto, a slide on which saidmeans supporting said chuck means is disposed, a cam means forlongitudinally displacing said means supporting said chuck means, saidchuck means having inner clamping members, spring means for biasing saidinner clamping members into a clamping locking position for retainingsaid work piece, and hydraulically operated knee lever means for movingsaid inner clamping members against the force of said spring means intoa releasing position.